Your best bet are the $40 WAVE ones in the clear packaging you get on eBay. They're probably the motaccurate colour wise too.
They sem to be more expensive than usual at the moment for some reason.
http://cgi.ebay.com/Ghost-Shell-Tachikoma-Metal-Ishikawa-Figure-WAVE_W0QQitemZ310101895799QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item310101895799&_trksid=p3286.c0.m14&_trkparms=72%3A1205|6
6%3A2|65%3A12|39%3A1|240%3A1318#ebayphotohosting
http://cgi.ebay.com/Ghost-In-The-Shell-SAC-1-24-Tachikoma-Blue-Figure-PVC_W0QQitemZ200272866808QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item200272866808&_trksid=p3286.c0.m14&_trkparms=72%3A1
205|66%3A2|65%3A12|39%3A1|240%3A1318
http://cgi.ebay.com/Ghost-in-the-Shell-1-24-PVC-Tachikoma-Tachi-Blue-Wave_W0QQitemZ120337295965QQcmdZViewItemQQptZLH_DefaultDomain_0?_trksid=p3286.m20.l1116#ebayphotohosting
http://cgi.ebay.com/Ghost-in-the-Shell-1-24-Tachikoma-Tachi-Silver-Wave_W0QQitemZ140276084496QQcmdZViewItemQQptZLH_DefaultDomain_0?_trksid=p3286.m20.l1116#ebayphotohosting
http://cgi.ebay.com/WHAM-GitS-SAC-1-24-Tachikoma-Yellow-Togusa-Figure-WAVE_W0QQitemZ310097548232QQcmdZViewItemQQptZLH_DefaultDomain_0?_trksid=p3286.m20.l1116
There's more if you look.